Establishment and phenotypic characterization of three new human myeloma cell lines (U-1957, U-1958, and U-1996)

Abstract

Three new human myeloma cell lines (U-1957, U-1958, and U-1996) have been established in vitro. The cell lines are Epstein-Barr virus (EBV) negative, monoclonal, and aneuploid and should thus represent malignant cell populations and not EBV-carrying non-neoplastic B lymphoblastoid cell lines. The myeloma origin of the cell lines is also suggested by their capacity for production of monoclonal complete immunoglobulin (Ig) molecules (U-1957 and U-1958) or IgG light chains (U-1996) of the same type as the myeloma protein in vivo. All the cell lines have morphological features of plasmablasts-plasma cells but appear to represent slightly different stages of B cell differentiation. Thus, the U-1958 has plasma cell morphology, expresses only PCA-1 and OKT-10 but no other B cell antigens, and secretes 1.5 micrograms/mL of IgG/10(6) cells/24 hours. The U-1957 has plasma cell morphology and expresses Fc receptors and the LB-1 antigen in addition to the PCA-1 and OKT-10 antigens. This line produces only minimal amounts of IgG, which appears not to be secreted. The U-1996, finally, is a kappa light chain producer, has a plasmablast morphology, and expresses LB-1 in addition to the PCA-1 and OKT-10 antigens. All three cell lines are chromosomally heterogeneous and contain several markers with a 14q+ abnormality as a common characteristic abnormality. These new myeloma lines have been in continuous culture for approximately 3 years and are instrumental in studies of various aspects of the biology of human myeloma.

Expression of the bcl‐2 family of pro‐ and anti‐apoptotic genes in multiple myeloma and normal plasma cells

“…The HL407L cell line grows both adherent and in suspension and express both IL‐6 protein and IL‐6 receptors (38). The U‐1958 (39) and U‐266–1970 (22, 40) cell lines grow both adherent and in suspension, and are dependent on IL‐6 for survival and/or growth (23, 37). Therefore, these cell lines are routinely grown on IL‐6 producing AG1523 fibroblasts (The Human Mutant Genetic Cell Repository, Camden, NJ, USA).…”

“…The IL‐6‐dependent MM cell lines U‐266–1970, U‐1958, and HL407L (23, 37, 39) and CD138+ non‐neoplastic plasma cells, isolated from human tonsils, were analysed by flow cytometry for the expression of Bcl‐2, Bcl‐xL/S, Mcl‐1, Bcl‐w, Bak, Bax, and Bad. The specificity of the polyclonal abs was confirmed by Western blot analysis.…”

Establishment of two interleukin 6 (B cell stimulatory factor 2/interferon beta 2)-dependent human bone marrow-derived myeloma cell lines.

“…Although autocrine mechanisms of myeloma cell growth have been documented by several authors (16,17), the establishment of spontaneously proliferating myeloma cell lines in vitro is extremely difficult (1). In addition to autocrine mechanisms, paracrine mechanisms have also been suggested to play an important role in myeloma cell growth (1,4,18,19).…”

“…Although autocrine mechanisms of myeloma cell growth have been documented by several authors (16,17), the establishment of spontaneously proliferating myeloma cell lines in vitro is extremely difficult (1). In addition to autocrine mechanisms, paracrine mechanisms have also been suggested to play an important role in myeloma cell growth (1,4,18,19). Our results agree with the paracrine mechanisms of myeloma cell growth ; bone marrow-derived myeloma cell lines proliferate in the presence of MOs, MDF is able to substitute for the M(b functions, Mos produce IL-6, myeloma cell lines most strongly proliferate in response to rIL-6, a-IL-6 antibody inhibits the rIL-6or MDFinduced proliferation of myeloma cell lines, and myeloma cell lines have been maintained for >1 yr in the medium containing rIL-6.…”

Human bone marrow stroma‐dependent cell line MOLP‐5 derived from a patient in leukaemic phase of multiple myeloma

“…Nilsson et al (1970) reported the establishment of a MM cell line, 266Bl later named U‐266, using a skin fibroblast monolayer. Other authors confirmed that fibroblast‐conditioned medium was able to stimulate the growth of human myeloma cells (Jobin et al , 1974; Jernberg et al , 1987). Kawano et al (1988) first showed that human myeloma cells proliferate in response to interleukin (IL)‐6.…”